(1) Field of the Invention
This invention relates to a combined writing tool of a mechanical pencil and a ball-point pen, of plural mechanical pencils from different lead diameters and/or lead colors with each other, and of plural ball-point pen with different ball diameters and/or ink colors, and in particular a thin-shaped combined writing tool.
(2) Description of the Prior Art
A conventional combined writing tool comprises a body and two ball-point pens with different colors with each other and a rotation cam mechanism including a can body, a rotation cam, and a cam bar wherein a head of one ball-point pen can be projected out of the forward end of the body alternately with the action of the rotation cam mechanism by knocking operation.
However, the conventional combined writing tool does not include only the mechanism for projecting the head of a ball-point pen out of the forward end of the body alternately by a knocking operation and does not have a mechanism for feeding lead out of a head of a mechanical pencil shaft. Further, because of the complicated construction of the rotation cam mechanism, it is impossible to select desired writing shaft promptly and also it is difficult to form a thin-shaped combined writing tool.